Dental Tribune Middle East & Africa No. 4, 2016

Dental Tribune Middle East & Africa Edition | 4/2016 24 general dentistry Treatment of the worn and spaced dentition – An ultraconservative, multidisciplinary approach ByDr.AndrewWakefield,UK Tooth surface loss (TSL) can present in various clinical forms and has a wide range of aetiological factors. Dental erosion, attrition and abra- sionarecommonlyobservedbygen- eral practitioners, the first two often being seen in younger patients. The superimposition of TSL and maloc- clusion and/or tooth size and posi- tion discrepancies can compound the problem because of the coinci- dent loss of form, function and aes- thetics. It can also create difficulties in planning treatment options, with treatment strategies having to be drawnfrommultipledisciplinesand integrated harmoniously to achieve long-term success. There are also other important issues to consider; treatment of tooth wear involves altering the vertical dimension of occlusion (VDO) and orthodontic treatment alters the position of the teeth, both often complex, lengthy and high cost procedures in their own right, never mind in combina- tion. If the patient is young the cost of ideal treatment can be prohibitive and they will expect longevity from the treatment provided and materi- als used. These are conflicts which probably will require some form of compromised treatment being embarked upon. It also needs to be borne in mind that the protection of valuable remaining natural tooth tissue is sacrosanct and this puts pressure on the ethical practitioner to be as conservative as possible. It is therefore crucial in these cases to ensure that the patient is fully aware of any compromises chosen, the rea- son behind the choices made and to involve them in the decision mak- ing process itself. Fortunately with the advent of modern hybrid nano- composite materials and innovative orthodontic and restorative tech- niques, treatment can be designed to be progressive in nature, with patient-led decision making. Success can be achieved at the straightfor- ward end of the treatment spectrum yet can evolve to encompass more complex restorative work involv- ing the skills of a dental technician if required. All of these factors had to be considered in the case presented here. CaseStudy The case study illustrates a simple multidisciplinary approach through the use of occlusal therapy combin- ing centric relation direct composite build-up of worn occlusal surfaces of upper and lower molars and premo- lars to re-establish an acceptable and comfortable VDO. The resulting in- crease in anterior space was utilised by retracting the spaced, severely worn upper incisors with removable aligners (IAS Inman Aligner and IAS Clear Aligners). This enabled aesthet- ic restoration without the need for invasive reduction by placing direct labial nano-hybrid composite ve- neers using a modified (untrimmed, full coverage) version of a clear ma- trixtechniquedescribedbyMizrahi1 . The patient first approached me when he was 21 years old, complain- ing of unsightly gaps between his front teeth. There was a relevant family history as he had an identical twin brother who also had a spaced anterior dentition. Extraorally he presented with a reduced lower face height. Intraoral examination showed evidence of moderate oc- clusal wear through to dentine oc- clusally on several upper and lower molars and premolars. The upper incisors were severely worn and had lost almost half of their clinical crownlength.Microdontiawasruled out, but the presence of diastemata indicated an imbalance between the jaw size and the size of the teeth. There was no serious frenal inter- ference. The palatal surfaces of the upper incisors and the edges of the lowerincisorswerereasonablyintact and there was a class 1 incisor rela- tionship and no deep bite. The labial surfacesofalltheteethwereunworn and the dentition unrestored. The upper canines were also worn and tilted slightly labially. It was pos- sible to identify an anterior slide of the mandible, functional contacts on the posterior teeth and an ab- sence of anterior guidance. There were no dietary abnormalities yet neither was he aware of any brux- ist activity, although he admitted a severe nail biting habit. A diagnosis of premature anterior attrition in the presence of unfavourable canine geometry coupled with non-tooth contact parafunction was made. The patient vanished for two years, then returned, eager to commence treat- ment. Study cast comparison was able to demonstrate that there had not been any appreciable change in the clinical situation during that time, possibly attributable to a de- crease in the rate of wear over time as the surface area of the teeth in contactincreases4 . Aimsoftreatment 1. To create a mutually protected occlusion where the anterior teeth disclude the posterior teeth in all ex- cursivemovementsofthemandible 2. To avoid any preparation to the teeth whilst providing treatment according to sound biomechanical principles 3.Topreventfurtherpathologicwear of all teeth and to cover all exposed dentine 4. To securely retain for life the posi- tions of the upper incisors after or- thodonticmovement 5. To improve the aesthetics and re- store the patient’s confidence in the appearanceofhissmile 6.Toperformthetreatmentinasen- sible time frame and as cost effec- tivelyaspossible Treatment plan FourPhases 1. To re-establish a stable posterior occlusion at an increased VDO us- ingcentricrelationandsimpledirect composites bonded onto the occlus- alsurfacesasanocclusaldeprogram- mer to discourage the anterior slide and allow the mandible to go back. This will also create space for the or- thodonticphase. 2. To retract the upper anterior teeth with removable aligners by a suf- ficient amount to enable their sub- sequent restoration to aesthetically acceptable mesio-distal dimensions and to create interproximal contact, but not so much as to encounter a problem with soft tissue squeeze. This would take approximately three-four months during which timethepatientwouldbeaccommo- datingtothenewVDOestablishedin phase 1. This will eliminate the need for invasive reduction of the incisors duringthenextphase. 3. To recreate the incisal anatomi- cal form using direct nano-hybrid composite labial veneers. Precision informwillbeassuredbyusingafull clear silicone stent made over a diag- nostic wax-up, with the wearing of a pre-evaluative temporary to assess patientcomfortandsatisfaction. 4. To retain the teeth in their new positions for life using a palatal wire bondedretainerlockedintothecom- posite veneers for added flexural strength. Treatment Progression The worn dentine and enamel on the occlusal surfaces of the upper and lower molars and premolars was covered and restored to original morphology with acid etch bond- ing and direct placement of nano- hybrid composite (Venus Pearl – Heraeus Kulzer). Even contacts were established in centric relation (not done definitively as the final adjust- ment of the occlusal scheme was performed later after the establish- ment of the anterior guidance). The increase in the VDO anteriorly was approximately2mm. A standard IAS Inman Aligner was fitted to the upper arch with the aim of retracting the incisors. This occurred over a four-month period, with IAS Clear Aligners used for refinement of position at the end. During this time the patient accom- modated very well to the new VDO. The 3D printed model of the pre- dicted outcome of the orthodontic phase proved doubly useful; first for consent, but also because a wax-up of the composite veneers could be performed on it in order to see if the retraction predicted would allow the subsequent placement of appropri- ately sized composite veneers which would have interproximal contact. Once the incisors had been retracted to the pre-planned position, an ac- curate wax-up was made on a study cast and a full coverage clear silicone matrix, strengthened by 1mm Essix Ace retainer material sucked down over it, was made1 . As the whole pro- cedure was additive and as it would make a profound difference to the patient’s appearance, a pre-evalua- tive temporary in a temp crown and bridge material was made. This was worn for a day and night and proved a functional, aesthetic and phonetic success, giving confidence when it came to the build-ups that the plan was achievable. The thickness of the temporaries was visualised on removal and they were retained for use as a guide to estimating the vol- ume and distribution of composite to load into the matrix. The compos- itesweredoneindividuallyusingthe full coverage matrix, with a single enamel shade of Venus pearl (A2 In- cisors, A3 Canines) over a small py- ramidal build-up5 of dentine shade OLC Venus pearl. Adjacent teeth were protected with PTFE tape dur- ing placement and the restorations finished on the labial surface with a combination of Sof-Lex discs and rubber composite polishing points and wheels. The palatal surface was leftunfinished.AnEssixretainerwas made on the spot for the patient to wear for a week while a lab-fabricat- ed palatal wire splint was made. At the fit stage, oval undercut cavities were prepared in the composite on the unpolished palatal surface into which flowable composite (Venus Diamond Flow – Heraeus Kulzer) was run as an adjunct to the etching and bonding of the wire to a large palatalareaoneachtooth. Discussion The treatment proved to be a suc- cessful, cost effective choice for the patient, primarily due to accurate planning,realisticexpectations,good compliance and avoidance of exces- sive laboratory fees. At six month re- call, there is no evidence of marginal breakdownofthecompositeandthe wire is still bonded and preventing relapse. The shape of the anteriors is now established and can be copied later if a move to ceramics is ever considered. In this type of additive Before treatment portrait Before treatment smile Waxupandmask Upperocclusalat endof treatment Portrait after treatment Crosssectionofincisorsafter treatment After increasing VDO with posterior occlusal buildup Before treatment upperocclusal Pre-evaluative temporaryinsitu Afterposteriorocclusalbuildupleft view Before treatment lowerocclusal Anteriorsat endof treatment Before treatment left sidesmile ÿPage 25 Join Inman Aligner Hands-On Courses at the 8th Dental Facial Cosmetic Int'l Conference! 05-06 Nov 2016 | Jumeirah Beach Hotel, Dubai, UAE